Affiliates' Research in Medical Journals, Spring 2024

Many NBER-affiliated researchers publish some of their health-related findings in journals that preclude pre-publication distribution, and thus do not post them as NBER Working Papers. This is a partial listing of recent papers in this category by NBER affiliates.

Estimates of Diagnosed Dementia Prevalence and Incidence among Diverse Beneficiaries in Traditional Medicare and Medicare Advantage
Haye S, Thunell J, Joyce G, Ferido P, Tysinger B, Jacobson M, Zissimopoulos J. Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring 15(3), August 2023.

For persons with dementia, receiving a diagnosis supports access to interventions to better manage symptoms and maintain quality of life, and helps families plan for financial and caregiving needs. Population estimates of diagnosed dementia also help plan for healthcare needs and expenditures for the entire population. While diagnosis rates can be seen in claims data for Medicare beneficiaries in the traditional program (TM), little was known about diagnosed dementia rates among beneficiaries enrolled in Medicare Advantage (MA), a private plan alternative chosen by about half of beneficiaries. The researchers thus undertook this study to quantify diagnosed dementia prevalence and incidence rates in MA for comparison to rates in TM, and to provide estimates for the entire Medicare population and for different racial/ethnic populations. They used newly available encounter data for those in MA, which include diagnoses from encounters and often additional diagnoses from chart reviews. The sample consisted of 32,032,275 beneficiaries aged 65 or older with Part D who were continuously enrolled in TM or MA for at least 2 years. Dementia was defined using an algorithm based on relevant International Classification of Diseases (ICD) 9 and 10 codes in all care settings, and Part D (pharmaceutical) claims for treatment of dementia symptoms. Adjusting for sociodemographic and health differences between the groups, the prevalence of diagnosed dementia was 8.7 percent among beneficiaries in TM and 7.1 percent among those in MA. The diagnosed dementia incidence rate was also lower in MA (2.50 percent) compared to TM (2.99 percent). These lower rates in MA were found among men, women, and White, Black, Hispanic, Asian, and American Indian/Alaska Native persons. These differences may point to how the structure of payments to MA plans create incentives for these plans to restrict the use of healthcare services and specialist referral services that may lead to the detection and diagnosis of dementia. Racial and ethnic minorities disproportionately enroll in MA plans relative to TM, and the lower rates for them in MA even when adjusting for this may exacerbate racial/ethnic disparities in diagnosed dementia. Diagnosed dementia prevalence and incidence for the entire Medicare population were 7.9 percent and 2.8 percent. This prevalence rate is lower than the 10 percent found in a nationally representative sample of older adults from the Health and Retirement Study and using the Harmonized Cognitive Assessment Protocol, suggesting 20 percent of the population may be undiagnosed. Having these rates as a baseline will enable tracking of diagnosis rates over time and also inform the response to policy changes, such as the risk adjustment for dementia reintroduced to MA in 2020.

The Camden Coalition Care Management Program Improved Intermediate Care Coordination: A Randomized Controlled Trial
Finkelstein A, Cantor JC, Gubb J, Koller M, Truchil A, Zhou RA, Doyle J. Health Affairs 43(1), January 2024.

A randomized evaluation of the Camden Coalition’s influential care management program, which targeted high-use, high-need patients in Camden, New Jersey, found that it did not reduce hospital readmissions, although evidence from prior nonrandomized trials suggested it did. This study investigates two potential explanations for the null result in the RCT. One is that the program’s underlying theory of change was not right, meaning that intensive care coordination may have been insufficient to change patient outcomes. Another is a failure of implementation, suggesting that the program may have failed to achieve its goals but could have succeeded if it had been implemented with greater fidelity. To test these two explanations, study participants were linked to Medicaid data, which covered 561 (70 percent) of the original 800 participants, to examine the program’s impact on facilitating post-discharge ambulatory care—a key element of care coordination. Multivariable linear regression compared outcomes between those randomly assigned to receive the program and those assigned to the control group, using the same controls as in the original trial. Though the program did not achieve its ultimate goal of reducing inpatient readmissions and emergency department visits, as reported in the original trial, it did have important effects on its intermediate care coordination goals, increasing the likelihood of receiving durable medical equipment and increasing ambulatory visits by 15 percentage points after 14 days post-discharge. The latter effect was driven by an increase in primary care, which persisted through 365 days. This effect is similar in size to those found in other studies of programs designed to increase ambulatory care in less complex patient populations. These results suggest that care coordination alone may be insufficient to reduce readmissions for patients with high rates of hospital admissions and medically and socially complex conditions. Consistent with this interpretation, the Camden Coalition and several large health systems are actively incorporating other supplemental supports into their care management models, such as providing housing and legal services, as part of a greater focus on nonclinical support. 

Prescription Drug Monitoring Program Use by Opioid Prescribers: A Cross-Sectional Study
Sacarny A, Williamson I, Merrick W, Avilova T, Jacobson M. Health Affairs Scholar 1(6), December 2023.

Clinician use of prescription drug monitoring programs (PDMPs) has been linked to better patient outcomes, but state requirements to use PDMPs are unevenly enforced. This study assessed PDMP use in Minnesota, which requires opioid prescribers to hold accounts and, in most cases, search the PDMP before prescribing, but where enforcement authority is limited. To identify Minnesota-based prescribers, National Plan and Provider Enumeration System data was used. Opioid prescriptions were identified using Centers for Disease Control and Prevention opioid data and drug-name field searches; the researchers divided clinicians into deciles by volume as measured by total opioid-days supplied. Using Minnesota PDMP data for the 180-day period starting February 1, 2023, the researchers found that 4 in 10 opioid prescribers did not search the PDMP, and 2 in 10 did not hold an account. PDMP use was strongly associated with prescribing volume: moving up 1 decile of opioid-prescribing volume was associated with a 6.7 percentage point increase in the probability of searching (P < .001) and a 3.2 percentage point increase in the probability of holding an account (P < .001). The vast majority of the highest-decile opioid prescribers searched the PDMP. Still, 7.8 percent of the highest-decile opioid prescribers did not search and 4.26 percent did not even have an account. Thirty-two percent of opioid fills came from clinicians who did not search the PDMP. The overrepresentation of low-volume prescribers in this group may reflect a lack of information about state mandates. That some of the highest-volume prescribers also do not use the PDMP, however, suggests that some prescribers believe that the mandate is not enforced and/or find the administrative burden of engaging with the PDMP high relative to the benefits. These results highlight the potential for policymakers to promote safer and better-informed prescribing of opioids and other drugs by addressing informational, administrative, and behavioral barriers that have limited PDMP use so far.

Medicare Part D Plans Greatly Increased Utilization Restrictions on Prescription Drugs, 2011-20
Joyce G, Blaylock B, Chen J, Van Nuys K. Health Affairs 43(3), March 2024, pp. 391–397.

The Adult Consequences of Being Bullied in Childhood
Blanchflower DG, Bryson A. Social Science & Medicine 345, March 2024.

Trends in Integration between Physician Organizations and Pharmacies for Self-Administered Drugs
Kakani P, Cutler DM, Rosenthal MB, Keating NL. JAMA Network Open 7(2), February 2024.

Hospital-Physician Integration and Clinical Volume in Traditional Medicare
Post B, Hollenbeck BK, Norton EC, Ryan AM. Health Services Research. 59(1), February 2024.

Effect of an Intensive Food-as-Medicine Program on Health and Health Care Use: A Randomized Clinical Trial
Doyle J, Alsan M, Skelley N, Lu Y, Cawley J. JAMA Internal Medicine 184(2), February 2024, pp. 154–163.

Why Does the Inflation Reduction Act Exclude Expensive Cancer Treatments in Price Negotiations?
Horn DM, Jacobson M, Alpert AE, Duggan MG. JCO Oncology Practice 20(2), February 2024, pp. 254–261.

Racial and Ethnic Disparities in Emergency Department Transfers to Public Hospitals
Hsuan C, Vanness DJ, Zebrowski A, Carr BG, Norton EC, Buckler DG, Wang Y, Leslie DL, Dunham EF, Rogowski JA. Health Services Research 59(2), January 2024.

Small Marketplace Premiums Pose Financial and Administrative Burdens: Evidence From Massachusetts, 2016-17
McIntyre A, Shepard M, Layton TJ. Health Affairs 43(1), January 2024, pp. 80–90.

Trends in Incident Dementia Diagnosis before and after Medicare Risk Adjustment
Zissimopoulos J, Joyce G, Jacobson M. JAMA Network Open 6(12), December 2023.

Prices for Common Services at Quaternary vs Nonquaternary Hospitals
Yan BW, Pany MJ, Dafny L, Chernew ME. JAMA 330(22), December 2023, pp. 2211–2213.

Revisiting the Effects of State Earned Income Tax Credits on Infant Health: A Quasi-experimental Study Using Contiguous Border Counties Approach
Qian H, Wehby GL. BMC Public Health 23, December 2023.

Why Higher Copayments for Opioids Did Not Reduce Use among Medicare Beneficiaries
Joyce G, Zhou B, Kaestner R. Health Economics 33(3), November 2023, pp. 466–481.

Changes in Children's Health Care Access and Utilization in the United States in the First 2 Years of the COVID-19 Pandemic
Lyu W, Wehby GL. Academic Pediatrics 23(8), November 2023, pp. 1572–1578.

Exposure to the Indian Ocean Tsunami Shapes the HPA-Axis Resulting in HPA “Burnout” 14 Years Later
Lawton R, Frankenberg E, Seeman T, Crimmins E, Sumantri C, Thomas D. PNAS 120(44), October 2023.

Effects of State Reinsurance Programs on Health Insurance Exchange Premiums and Insurer Participation
Oyeka O, Wehby GL. Health Services Research 58(5), October 2023, pp. 1077–1088.

Children’s Oral Health and Oral Health Care Use during the First 2 Years of the COVID-19 Pandemic
Lyu W, Wehby GL. Journal of the American Dental Association 154(10), October 2023, pp. 930–936.

Cost of Public Health Insurance for US-Born and Immigrant Adults
Kaushal N, Muchomba FM. JAMA Network Open 6(9), September 2023.

Association Between Gestational Age and Academic Achievement of Children Born at Term
Wehby GL. JAMA Network Open 6(7), July 2023.

Part D Beneficiaries' Incentives and Responses under Preferred Pharmacy Networks
Xu J, Trish E, Joyce G. The American Journal of Managed Care 29(4), April 2023, pp. 180–186.